func generateData() {
fmt.Printf("(launching mock dump0190 on localhost:%d; mlat=%v)\n", port, mlat)
ln, _ := net.Listen("tcp", fmt.Sprintf("localhost:%d", port))
outerLoop:
for {
conn, _ := ln.Accept()
fmt.Printf("(connection started)\n")
m := adsb.Msg{
Icao24: adsb.IcaoId("A81BD0"),
Callsign: "ABW123",
Type: "MSG",
Altitude: 12345,
GroundSpeed: 300,
Track: 315,
VerticalRate: 64,
Position: geo.Latlong{36.0, -122.0},
GeneratedTimestampUTC: time.Now().UTC(),
LoggedTimestampUTC: time.Now().UTC(),
}
// We need to prime the pump, and trick the msgbuffer
m.SubType = 3 // Get an entry in the sender table for our Icao, by proving we have pos data
conn.Write([]byte(fmt.Sprintf("%s\n", m.ToSBS1())))
m.SubType = 1 // Populate the sender table entry with a callsign (MSG,1 only)
conn.Write([]byte(fmt.Sprintf("%s\n", m.ToSBS1())))
m.SubType = 4 // Populate the sender table entry with velocity data (MSG,4 only)
conn.Write([]byte(fmt.Sprintf("%s\n", m.ToSBS1())))
m.SubType = 3 // All future messages are linear position updates (MSG,3 only)
for {
now := time.Now().UTC().Add(-1 * delay)
m.Position.Lat += 0.01
m.GeneratedTimestampUTC = now
m.LoggedTimestampUTC = now
if mlat {
m.Type = "MLAT"
}
if _, err := conn.Write([]byte(fmt.Sprintf("%s\n", m.ToSBS1()))); err != nil {
fmt.Printf("(connection ended)\n")
continue outerLoop
}
time.Sleep(time.Millisecond * 1000)
}
}
}
